Dynamic regulation resonant power converter

ABSTRACT

According to one configuration, a power system includes a resonant power converter, a monitor resource, and a controller. During operation, the resonant power converter converts an input voltage to an output voltage. The monitor resource monitors a magnitude of the input voltage. The controller dynamically controls a corresponding resonant frequency of the resonant power converter and a switching frequency of switches in the resonant power converter depending on a magnitude of the input voltage.

RELATED APPLICATION

This application is a continuation in part application of earlier filedU.S. patent application Ser. No. 16/655,450 entitled “DYNAMIC REGULATIONRESONANT POWER CONVERTER,”, filed on Oct. 17, 2019, the entire teachingsof which are incorporated herein by this reference.

BACKGROUND

Conventional CPUs (Central Processing Units), GPUs (Graphics ProcessingUnits) and processors, for Artificial Intelligence (AI) chips requiremuch higher currents and have a very high dynamic load profile andoperate at significantly lower supply voltages compared to well-knownCPUs having an integrated Voltage regulator module.

With increasing power consumption and lower input voltages of arespective VRM (Voltage Regulated Module) power stage, the classicarchitecture of providing 12V throughout the motherboard reaches itslimitations. Modern hyperscale datacenter architectures typicallyoperate on 48V DC, which is distributed by central power suppliesthroughout a respective rack. Certain modern processors run on 0.9Vinput voltage and have linear on-board voltage regulators to adjust thesupply voltage of individual cores along their multi-chip solution.

BRIEF DESCRIPTION

This disclosure includes the observation that conventional powerconverters (such as intermediate bus converters) suffer fromdeficiencies. For example, certain power converters such as those thatapply relatively low or no regulation are quite efficient when a inputvoltage is maintained within a narrow input voltage range. However,power converters typically must be designed to accommodate a wide rangeof input voltages. Without sufficient regulation outside of the narrowinput voltage range, the magnitude of the output voltage falls outside adesirable narrow output voltage range.

Embodiments herein provide novel and improved efficiency of generatingan output voltage via a resonant power converter over a wide range ofinput voltages.

More specifically, a power system as described herein includes aresonant power converter, a monitor resource, and a controller. Duringoperation, the resonant power converter receives an input voltage andconverts it into an output voltage. The monitor resource monitors amagnitude of the input voltage. Depending on a magnitude of the inputvoltage, the controller controls a respective gain provided by theresonant power converter to convert the input voltage to the outputvoltage.

Adjusting a gain provided by the resonant power converter depending on amagnitude of the input voltage as described herein provides moreefficient conversion from an input voltage to an output voltage. Forexample, in most instances, the resonant power converter operates in arange of input voltage around an expected average value or narrow inputvoltage range. Embodiments herein include controlling the resonant powerconverter to operate in a highly efficient mode during conditions whenthe input voltage resides in the narrow or normal voltage range. When amagnitude of the input voltage falls outside the normal range, theoutput voltage would deviate if the resonant power converter wereoperated in the same gain mode implemented for the narrow input voltagerange. In one embodiment, although less efficient outside the narrowrange, the controller operates the resonant power converter in a highergain mode to maintain the magnitude of the output voltage within adesired range.

Note that the controller can be configured to control any suitable oneor more control parameters of the resonant power converter to maintainthe magnitude of the output voltage within a desired range. For example,in yet further embodiments, the controller dynamically controls aswitching frequency of switches in the resonant power converterdepending on a magnitude of the input voltage. The controller alsodynamically controls a magnitude of a corresponding resonant frequencyof the resonant power converter depending on a magnitude of the inputvoltage. Dynamic control of the switching frequency and the resonantfrequency associated with the resonant power converter as describedherein maintains a magnitude of the output voltage within a desiredvoltage range.

One embodiment herein includes producing map information. The mapinformation provides a mapping between the magnitude of the inputvoltage and a setting of the switching frequency applied to switches inthe resonant power converter. Via the map information, the controllermaps the magnitude of the input voltage to a switching frequency value.The controller then sets the identified switching frequency ofcontrolling the switches to the switching frequency value.

Additionally, or alternatively, further embodiments herein includeassigning each of multiple input voltage ranges a different resonantfrequency setting. For example, embodiments herein include dividing aninput voltage range (in which the input voltage may reside) intomultiple input voltage ranges; and assigning a respective resonantfrequency setting to each of the multiple input voltage ranges. Furtherembodiments herein can include implementing hysteresis to switch fromone resonant frequency setting to another resonant frequency settingdepending on whether a controller increases or decreases the resonancefrequency setting. In one embodiment, it is desirable to avoid that thesystem constantly jumps between two values when operating at an inputvoltage where we would change the resonance frequency setting.

During operation, the controller detects a particular voltage range (ofthe multiple voltage ranges) in which the magnitude of the input voltageresides. In one embodiment, as previously discussed, each of the voltageranges is assigned a respective resonant frequency setting. In such aninstance, the controller identifies a resonant frequency settingassigned to the particular voltage range. The controller then controlsthe resonant power converter to operate at the identified resonantfrequency setting assigned to the first voltage range.

Adjustment of the resonant frequency of the resonant power converter caninclude any suitable technique such as one or more of the following:adjusting a resonant capacitor component associated with the resonantcircuit, such as adjusting a resonant inductor component associated withthe resonant circuit, etc.

Additionally, or alternatively, note that the controller can beconfigured to control the resonant frequency of the resonant powerconverter circuit to be a fixed resonant frequency setting duringconditions in which the magnitude of the input voltage falls within theparticular voltage range of the multiple voltage ranges.

In yet further embodiments, to maintain the output voltage within adesired range, the controller varies a magnitude of the switchingfrequency as a magnitude of the input voltage varies within theparticular voltage range.

Further embodiments herein include, while a magnitude of the switchingfrequency is set to a fixed value, via the controller, varying amagnitude of the resonant frequency depending on variations of themagnitude of the input voltage.

In accordance with further embodiments, the resonant power converterincludes a first switch and a second switch. During operation, thecontroller controls switching of the first switch to selectively apply afirst voltage (such as the input voltage) to an input of a resonantcircuit of the resonant power converter; the controller controlsswitching of the second switch to selectively apply a second voltage(such as a ground reference voltage with respect to the input voltage)to the input of the resonant frequency circuit of the resonant powerconverter circuit.

In yet further embodiments, the multiple input voltage ranges include atleast a first input voltage range and a second input voltage range. Thefirst input voltage range is assigned a first resonant frequencysetting; the second input voltage range is assigned a second resonantfrequency setting. In such an embodiments, and as further discussedherein, a gain of the resonant power converter is a piece-wise gainfunction including a first gain function associated with the first inputvoltage range and a second gain function associated with the secondinput voltage range. In one embodiment, a magnitude of the first gainfunction and a magnitude of the second gain function is substantiallyequal at a transition between the first input voltage range and thesecond input voltage range.

Further embodiments herein include a power system comprising: a monitorresource and a controller. The monitor resource is operative to monitora magnitude of a voltage at a node of a resonant power converter. Thecontroller is operative to, depending on the magnitude of the voltage atthe node, dynamically control a respective gain provided by the resonantpower converter.

In further example embodiments, the controller determines a switchingfrequency in which to control switches in the resonant power converterbased on a combination of a resonant frequency of the resonant powerconverter and the magnitude of the voltage at the node. Operation of theresonant power converter at the resonant frequency and the determinedswitching frequency controls the respective gain of the resonant powerconverter.

Further embodiments herein include, via the controller or other suitableentity, mapping the magnitude of the voltage to a switching frequencyvalue and setting a switching frequency of controlling switches in theresonant power converter to the switching frequency value.

In still further example embodiments, via the controller, depending onthe magnitude of the monitored voltage, and to provide the respectivegain, adjusting a resonant frequency of the resonant power converter. Inone embodiment, this includes, via the controller or other suitableentity: i) detecting a first voltage range in which the magnitude of thevoltage resides, the first voltage range being one of multiple voltageranges associated with operation of the resonant power converter; ii)identifying a resonant frequency setting assigned to the first voltagerange; and iii) controlling the resonant power converter to operate atthe identified resonant frequency setting. In one nonlimiting exampleembodiment, each of the multiple voltage ranges is assigned a differentresonant frequency setting.

Still further example embodiments herein include, via the controller,controlling a resonant frequency of the resonant power converter to be afixed resonant frequency setting during conditions in which themagnitude of the voltage falls within a first voltage range; and varyinga magnitude of a switching frequency applied to switches in the resonantpower converter depending on the magnitude of the voltage within thefirst voltage range.

In yet further example embodiments, the controller is operative to set amagnitude of a switching frequency of operating switches in the resonantpower converter to a fixed value. The controller varies a magnitude of aresonant frequency of the resonant power converter depending onvariations in the magnitude of the voltage. In one embodiment, a voltagerange of the resonant power converter is split into multiple voltageranges, each voltage range of the multiple voltage ranges being assigneda respective resonant frequency setting.

Further embodiments herein include a power system comprising: a resonantpower converter to convert an input voltage to an output voltage; amonitor resource operative to monitor a magnitude of the input outputvoltage; a controller operative to, depending on the magnitude of theinput output voltage, dynamically control both a resonant frequency anda switching frequency of controlling switches in the resonant powerconverter to produce the output voltage, operation of the resonant powerconverter at the resonant frequency and the switching frequency settinga respective gain provided by the resonant power converter; and whereinthe controller is operative to calculate the switching frequency basedon a combination of the resonant frequency and the magnitude of theinput output voltage.

In still further example embodiments, a power system comprising: aresonant power converter to convert an input voltage to an outputvoltage; a monitor resource operative to monitor a magnitude of theinput output voltage; and a controller operative to, depending on themagnitude of the input output voltage and a resonant frequency of theresonant power converter, control a respective gain provided by theresonant power converter, the controller further operative to providesemi-regulated control of converting the input voltage into the outputvoltage, the semi-regulated control operated between a fully regulatedoperational mode and a fully unregulated operational mode.

Yet further example embodiments herein include a power systemcomprising: a resonant power converter to convert an input voltage to anoutput voltage; a monitor resource operative to monitor a magnitude ofthe input voltage; a controller operative to, depending on the magnitudeof the input voltage, dynamically control both a resonant frequency anda switching frequency of controlling switches in the resonant powerconverter to produce the output voltage, operation of the resonant powerconverter at the resonant frequency and the switching frequency settinga respective gain provided by the resonant power converter; and whereinthe controller is operative to calculate the switching frequency basedon a combination of the resonant frequency and the magnitude of theinput voltage.

These and other more specific embodiments are disclosed in more detailbelow.

Note that any of the resources implemented in system as discussed hereincan include one or more computerized devices, controllers, monitors,mobile communication devices, handheld or laptop computers, or the liketo carry out and/or support any or all of the method operationsdisclosed herein. In other words, one or more computerized devices orprocessors can be programmed and/or configured to operate as explainedherein to carry out the different embodiments as described herein.

Yet other embodiments herein include software programs to perform thesteps and operations summarized above and disclosed in detail below. Onesuch embodiment comprises a computer program product including anon-transitory computer-readable storage medium (i.e., any computerreadable hardware storage medium) on which software instructions areencoded for subsequent execution. The instructions, when executed in acomputerized device (hardware) having a processor, program and/or causethe processor (hardware) to perform the operations disclosed herein.Such arrangements are typically provided as software, code,instructions, and/or other data (e.g., data structures) arranged orencoded on a non-transitory computer readable storage medium such as anoptical medium (e.g., CD-ROM), floppy disk, hard disk, memory stick,memory device, etc., or other a medium such as firmware in one or moreROM, RAM, PROM, etc., or as an Application Specific Integrated Circuit(ASIC), etc. The software or firmware or other such configurations canbe installed onto a computerized device to cause the computerized deviceto perform the techniques explained herein.

Accordingly, embodiments herein are directed to a method, system,computer program product, etc., that supports operations as discussedherein.

One embodiment includes a computer readable storage medium and/or systemhaving instructions stored thereon to produce an output voltage. Theinstructions, when executed by computer processor hardware, cause thecomputer processor hardware (such as one or more co-located ordisparately located processor devices or hardware) to: monitor amagnitude of an input voltage supplied to a resonant power converter;set a resonant frequency of the resonant power converter depending on amagnitude of the input voltage; and dynamically control a switchingfrequency of switches in the resonant power converter depending on amagnitude of the input voltage, the resonant power converter convertingthe input voltage into an output voltage.

The ordering of the steps above has been added for clarity sake. Notethat any of the processing steps as discussed herein can be performed inany suitable order.

Other embodiments of the present disclosure include software programsand/or respective hardware to perform any of the method embodiment stepsand operations summarized above and disclosed in detail below.

It is to be understood that the system, method, apparatus, instructionson computer readable storage media, etc., as discussed herein also canbe embodied strictly as a software program, firmware, as a hybrid ofsoftware, hardware and/or firmware, or as hardware alone such as withina processor (hardware or software), or within an operating system or awithin a software application.

Note further that although embodiments as discussed herein areapplicable to switching power supplies, the concepts disclosed hereinmay be advantageously applied to any other suitable topologies.

Additionally, note that although each of the different features,techniques, configurations, etc., herein may be discussed in differentplaces of this disclosure, it is intended, where suitable, that each ofthe concepts can optionally be executed independently of each other orin combination with each other. Accordingly, the one or more presentinventions as described herein can be embodied and viewed in manydifferent ways.

Also, note that this preliminary discussion of embodiments herein (BRIEFDESCRIPTION OF EMBODIMENTS) purposefully does not specify everyembodiment and/or incrementally novel aspect of the present disclosureor claimed invention(s). Instead, this brief description only presentsgeneral embodiments and corresponding points of novelty overconventional techniques. For additional details and/or possibleperspectives (permutations) of the invention(s), the reader is directedto the Detailed Description section (which is a summary of embodiments)and corresponding figures of the present disclosure as further discussedbelow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an example diagram illustrating a power supply (power system)including a resonant power converter according to embodiments herein.

FIG. 2 is an example diagram illustrating details of a resonant powerconverter and a corresponding controller according to embodimentsherein.

FIG. 3 is an example graph illustrating a magnitude of an output voltageover a range of different magnitudes of an input voltage according toembodiments herein.

FIG. 4 is an example graph illustrating a gain of a resonant powerconverter over a range of different magnitudes of an input voltageaccording to embodiments herein.

FIG. 5 is an example graph illustrating gain functions associated withdifferent resonant frequency settings of a resonant power converter overa range of different magnitudes of an input voltage according toembodiments herein.

FIG. 6 is an example graph illustrating a attributes of a piece-wisegain function over a range of different magnitudes of an input voltageaccording to embodiments herein.

FIG. 7 is an example diagram illustrating of map information used tocontrol operation of a resonant power converter according to embodimentsherein.

FIG. 8 is an example diagram illustrating adjustment of a switchingfrequency and/or a gain of a resonant power converter according toembodiments herein.

FIG. 9 is an example diagram illustrating adjustment of a switchingfrequency and/or a gain of a resonant power converter according toembodiments herein.

FIG. 10 is an example diagram illustrating example computer architectureoperable to execute one or more methods according to embodiments herein.

FIG. 11 is an example diagram illustrating a method according toembodiments herein.

FIG. 12 is an example diagram illustrating a method according toembodiments herein.

FIG. 13 is an example diagram illustrating fabrication of a circuitboard including the novel power system according to embodiments herein.

FIG. 14 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode without changing a resonantfrequency according to embodiments herein.

FIG. 15 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode without changing a resonantfrequency but with optimized resonant tank circuit according toembodiments herein.

FIG. 16 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode with changes to a resonant frequencyaccording to embodiments herein.

FIG. 17 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode with changes to a resonant frequencybut with optimized resonant tank circuit according to embodimentsherein.

FIG. 18 is an example diagram illustrating a power supply (power system)including a resonant power converter according to embodiments herein.

FIG. 19 is an example diagram illustrating details of a resonant powerconverter and a corresponding controller according to embodimentsherein.

FIG. 20 is an example graph illustrating a magnitude of an outputvoltage over a range of different magnitudes of an input voltageaccording to embodiments herein.

FIG. 21 is an example graph illustrating a gain of a resonant powerconverter over a range of different magnitudes of an output voltageaccording to embodiments herein.

FIG. 22 is an example graph illustrating gain functions associated withdifferent resonant frequency settings of a resonant power converter overa range of different magnitudes of an output voltage according toembodiments herein.

FIG. 23 is an example graph illustrating a attributes of a piece-wisegain function over a range of different magnitudes of an input voltageaccording to embodiments herein.

FIG. 24 is an example diagram illustrating of map information used tocontrol operation of a resonant power converter according to embodimentsherein.

FIG. 25 is an example diagram illustrating adjustment of a switchingfrequency and/or a gain of a resonant power converter according toembodiments herein.

FIG. 26 is an example diagram illustrating adjustment of a switchingfrequency and/or a gain of a resonant power converter according toembodiments herein.

FIG. 27 is an example diagram illustrating a method according toembodiments herein.

FIG. 28 is an example diagram illustrating a method according toembodiments herein.

FIG. 29 is an example diagram illustrating a method according toembodiments herein.

FIG. 30 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode without changing a resonantfrequency according to embodiments herein.

FIG. 31 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode without changing a resonantfrequency but with optimized resonant tank circuit according toembodiments herein.

FIG. 32 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode with changes to a resonant frequencyaccording to embodiments herein.

FIG. 33 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode with changes to a resonant frequencybut with optimized resonant tank circuit according to embodimentsherein.

The foregoing and other objects, features, and advantages of embodimentsherein will be apparent from the following more particular descriptionherein, as illustrated in the accompanying drawings in which likereference characters refer to the same parts throughout the differentviews. The drawings are not necessarily to scale, with emphasis insteadbeing placed upon illustrating the embodiments, principles, concepts,etc.

DETAILED DESCRIPTION

Now, with reference to the drawings, FIG. 1 is an example diagramillustrating a power supply including a resonant power converter andcorresponding controller according to embodiments herein.

As shown in this example embodiment, the power system 100 (i.e., powersupply) includes controller 140 and resonant power converter 150. In oneembodiment, the power system 100 receives an input voltage and deliversan output voltage. The load can be a power converter 195 as shown or canbe directly a load such as a CPU with an integrated VRM. Note thatembodiments herein can include piece-wise adjusting of the resonancefrequency of the resonant power converter 150 depending on a magnitudeof the input voltage 120, but providing full regulation within each ofthe input voltage regions. Embodiments herein include supplying theoutput voltage 123 directly to any kind of load.

The resonant power converter 150 can be any suitable type of powerconverter. For example, the power converter as described herein can beimplemented in accordance with any isolated or non-isolated technology.

Examples of isolated power converter topologies include hard switchinghalf bridge converters, LLC converters, phase shift ZVS (Zero VoltageSwitching) converters, etc. Examples of non-isolated topologies includebuck converters, switched capacitor converters, tapped inductor switchedtank converters, combination converters such as buck/switched capacitorconverters, etc.

In one embodiment, the resonant power converter 150 is a semi-regulatedbus converter operative to convert the input voltage 120 into the outputvoltage 123. In such an instance, the amount of voltage regulationprovided by the controller 140 varies depending on a magnitude of theinput voltage. Note that further embodiments herein can includeproviding full regulation via a piece-wise set resonance frequencybands.

Note further that, in one embodiment, the controller 140 furtherincludes monitor resource 141 and corresponding map information 138.During operation, as previously discussed, the resonant power converter150 receives an input voltage 120 and converts it into an output voltage123. As its name suggests, the monitor resource 140 monitors a magnitudeof the input voltage 120. Depending on a magnitude of the input voltage120, the controller 140 controls a respective parameter such as gainprovided by the resonant power converter 150.

Thus, embodiments herein include adjusting a gain provided by theresonant power converter 150 depending on a magnitude of the inputvoltage 120 as monitored by the monitor resource 140.

In one embodiment, the gain associated with the resonant power converter150 determines the voltage conversion ratio of the resonant powerconverter 150.

For example, the output voltage 123 (i.e., Vout),Vout=Vin*Ns/Np*Gain,

where Vin is the input voltage 120, Ns=number of turns of the secondarywinding associated with the transformer T1, Np=number of turns on theprimary winding associated with the transformer T1, Gain is the gainprovided by the resonant power converter 150.Gain=(Vout/Vin)*(Np/Ns),

or more generally, Gain=(Vout/Vin)*Scale-Factor, where the scale factoris any suitable value chosen to convert an input voltage within an inputvoltage range to a respective output voltage in a desired output voltagerange.

Adjusting the gain (such as Vin times some scale factor) associated withthe resonant power converter 150 provides more efficient conversion ofthe input voltage 120 to an output voltage 123 for varying input voltagesettings. In one embodiment, embodiments herein include operating theresonant power converter 150 as close as possible to a gain of around 1to maximize efficiency.

More specifically, assume that for a majority of time, the resonantpower converter 150 receives an input voltage 120 that is close in value(such as within 5% of point) to an expected average value such as 48VDC. In such an instance, conversion efficiency is very high. As furtherdiscussed herein, embodiments herein include controlling the resonantpower converter 150 to operate in a highly efficient low gain modeduring conditions when the input voltage resides in a normal voltagerange such as between 45 VDC and 53 VDC. When a magnitude of the inputvoltage falls outside this normal range (such as when the input voltage120 is greater than 53 VDC or less than 46 VDC), the output voltage 123would deviate if the resonant power converter were operated in the mostefficient gain mode close to a gain of 1 associated with the normalvoltage range as previously discussed. In accordance with embodimentsherein, although less efficient, in order provide better regulation ofthe output voltage 123 (such as an output voltage closer to a desiredtarget value without providing full regulation, which is lessefficient), the controller 140 operates the resonant power converter 150in a non-unity gain mode (where the gain is substantially higher thanone or substantially lower than one when the input voltage 120 fallsoutside the normal range to maintain the magnitude of the output voltage123 within a desired range. Further details are discussed below.

Note that the controller 140 can be configured to control any suitableone or more control parameters of the resonant power converter 150 tomaintain the magnitude of the output voltage 123 within a desired range.The power system 100 supplies the output voltage 123 to any suitableload or power converter 195, which further converts the output voltage123 into a highly regulated supply voltage that powers a load.

For example, in one embodiment, depending on the magnitude of the inputvoltage 120, the controller 140 dynamically controls parameters such as:i) a switching frequency of switches in the resonant power converter,ii) a resonant frequency of the resonant power converter 150, etc.

Dynamic control of the switching frequency and/or the resonant frequencyoperation associated with the resonant power converter 150 maintains amagnitude of the output voltage 123 within a desired voltage range,closer to a desired target DC voltage value.

Note further that embodiments herein optionally include producing mapinformation 138. When implemented, the map information 138 provides amapping between the magnitude of the input voltage 120 and a setting ofthe switching frequency applied to one or more switches in the resonantpower converter 150. Thus, via the map information 138, as furtherdiscussed herein, the controller 140 maps the current magnitude of theinput voltage 120 to a resonant frequency value and sets the resonantfrequency operation of the resonant power converter 150 to the resonantfrequency value.

Additionally, or alternatively, the controller 140 maps the currentmagnitude of the input voltage 120 to an appropriate switching frequencyvalue, Fsw. The controller 140 then sets the switching frequency of theresonant power converter 120 to the switching frequency value.

FIG. 2 is an example diagram illustrating details of a resonant powerconverter and a corresponding controller according to embodimentsherein.

As shown, the power system 100 includes controller 140, input voltagesource Vin, switches S1 and S2, capacitor Cr, inductor Lr, transformerT1 (such as a tapped-transformer), diode D1, diode D2, capacitor Co, andresistor R.

As previously discussed, the controller 140 includes monitor resource141 and map information 138.

Further in this example embodiment, as shown, the switches S1 and S2 arecoupled in series between the input voltage source Vin and correspondingground reference. For example, the drain node (D) of the switch S1 iscoupled to the input voltage source Vin. At node 281, the source node(S) of switch S1 is coupled to the drain node (D) of switch S2 as wellas a corresponding node of capacitor Cr.

The source node (S) of switch S2 is coupled to the ground referencevoltage.

The controller 140 is coupled to drive the control signal 105-1 to thegate node (G) of switch S1; the controller 140 is coupled to drive thecontrol signal 105-2 to the gate node (G) of switch S2.

As further shown, resonant circuit 250 such as the combination of thecapacitor Cr, inductor Lr, and primary winding 261 of the transformer T1are connected in series between node 281 and ground. Inductor Lmrepresents the magnetizing inductance associated with the primarywinding 261 of transformer T1.

The primary winding of T1 is magnetically coupled to both secondarywinding 262-1 and secondary winding 262-2. If desired, node 292 (such astap associated with the transformer T1) can be connected to ground. Eachof the primary winding 261 and secondary windings 262 can include anysuitable number of turns. In one nonlimiting example embodiment, thewindings include an appropriate number of turns such that the resonantpower converter 150 converts, on average, an input voltage 123 of 48 VDCinto an output voltage of 6 VDC, although the resonant power converter150 can be configured to provide any suitable voltage conversion.

Yet further, diode D1 is connected between the node 291 of thetransformer T1 and the output voltage node 283. Diode D2 is connectedbetween the node 293 of the transformer T1 and the output voltage node283.

Finally, capacitor Co is coupled between the output voltage node 283 inthe node 292. Resistor R is connected between the output voltage node283 and the node 292.

Thus, in this example embodiment shown, the resonant power converter 150includes a first switch S1 and a second switch S2.

During operation, the controller 140 controls switching of the firstswitch S1 to selectively apply a first voltage (such as the inputvoltage 120) to an input (node 281) of the resonant circuit 250 of theresonant power converter 150; the controller 140 controls switching ofthe second switch S2 to selectively apply a second voltage (such as aground reference voltage with respect to the input voltage) to the input(node 281) of the resonant circuit 250 of the resonant power convertercircuit 150.

In accordance with further embodiments, switching of the switches S1 andS2 during each of multiple control cycles includes a first switchsetting of activating the switch S1 (providing a low resistive pathbetween respective source and drain nodes) for a duration of time whileswitch S2 is deactivated (providing a high resistive path). Switching ofthe switches S1 and S2 during each of multiple control cycles furtherincludes a second switch setting such as activating the switch S2(providing a low resistive path between respective source and drainnodes) for a duration of time while switch S1 is deactivated (providinga high resistive path). The controller 140 repeatedly switches betweenthe first switch setting and the second switch setting to convert theinput voltage 120 into the output voltage 123.

As previously discussed, the map information 138 provides a mappingbetween the magnitude of the input voltage 120 and a setting of theresonant frequency associated with operating the resonant powerconverter 150. Thus, via the map information 138, the controller 140maps the current magnitude of the input voltage 120 to a resonantfrequency value and sets the resonant frequency operation of theresonant power converter 150 (specifically resonant circuit 250) to theselected resonant frequency value.

In one embodiment, control of the resonant frequency associated with theresonant circuit 250 can be achieved in any suitable manner. Forexample, any of one or more components capacitor Cr, inductor Lr, andinductor Lm can be adjusted to change a resonant frequency of theresonant circuit 250.

Additionally, or alternatively, as further discussed herein, thecontroller 140 maps the current magnitude of the input voltage 120 to aswitching frequency value, Fsw, associated with controlling switches S1and S2. For example, the controller 140 sets the switching frequency(Fsw) of producing the control signals 105-1 and 105-2 of the resonantpower converter 120 to the selected switching frequency value (Fsw).

Again, in one embodiment, the gain associated with the resonant powerconverter 150 determines the voltage conversion ratio of the LLC(together with the transformer T1 turn ratio).

For example, the output voltage 123 (i.e., Vout),Vout=Vin*Ns/Np*Gain,

where Vin is the input voltage 120, Ns=number of turns of the secondarywinding associated with the transformer T1, Np=number of turns on theprimary winding associated with the transformer T1, Gain is the gainprovided by the resonant power converter 150.Gain=(Vout/Vin)*(Np/Ns)

FIG. 3 is an example graph illustrating operation of a resonant powerconverter over a range of different magnitudes of input voltageaccording to embodiments herein.

Conventional techniques include implementation of function 310 orfunction 330 to generate a respective output voltage. For example, whenthe conventional power converter function 330 (full regulation) isimplemented to convert an input voltage into an output voltage, theoutput voltage is a constant target voltage (such as 6 VDC) regardlessof a magnitude of the input voltage. When the function 310 (fullyunregulated mode) is implemented to convert an input voltage into anoutput voltage, the output voltage linearly varies depending on amagnitude of the input voltage 120. As further discussed herein, thecontroller 140 is operative to provide semi-regulated control (mode 320)of converting the input voltage 120 into the output voltage 123, thesemi-regulated control operated between a fully unregulated operationalmode (310) and a fully regulated operational mode (330).

Embodiments herein include implementation of an advanced transferfunction 320 (semi-regulated output) as shown in graph 300. In this casethe converter would provide little to no regulation in a central band350 of input voltage values, while providing semi-regulation both at theupper end (such as input voltages greater than band 350) and lower end(such as input voltages less than band 350) of the full input voltagerange between 40 and 60 VDC. In this case, operation of a powerconverter 150 as described herein in band 350 provides high efficiency,which is operation for a majority of time in which the resonant powerconverter 150 converts the input voltage 120 into the output voltage123. Operation outside the band 350 is slightly less efficient, butprovides better regulation of the output voltage 123 than does the fullyunregulated function 310. Accordingly, embodiments herein includeproviding varying degrees of regulation depending on a magnitude of theinput voltage 120 and which of multiple different input voltage rangesthe magnitude falls. In one embodiment, the term degrees of regulationmeans how fast gain is adjusted as a function of varying input voltage

FIG. 4 is an example graph illustrating operation of a resonant powerconverter over a range of different magnitudes of input voltageaccording to embodiments herein.

Graph 400 illustrates example gain 420 associated with the resonantpower converter 150 over a range of different input voltage values suchas between 40 VDC and 60 VDC. As shown, gain 420 falls between gain 410associated with a fully unregulated power converter and gain 430associated with a fully regulated power converter.

FIG. 5 is an example graph illustrating operation of a resonant powerconverter over a range of different magnitudes of input voltageaccording to embodiments herein.

Further embodiments herein include splitting the input voltage range(such as between 40 VDC and 60 VDC) associated with the resonant powerconverter 150 into any number of ranges. In this example embodiment, theinput voltage range associated with the resonant power converter 150 issplit into multiple ranges such as range #1, range #2, range #3.

Yet further embodiments herein include assigning each of the multiplevoltage ranges a different resonant frequency setting. In such aninstance, the resonant power converter 150 provides a different gainfunction when converting the input voltage 120 into an output voltage123.

Note that embodiments herein include not only adjusting the resonantfrequency setting. For example, embodiments herein include adjusting thegain function as shown in FIG. 5. This typically includes changing theratio of Lr/Lm of the converter. In one embodiment, there are threedifferent operating ranges with distinctly different gain functions.

For example, for a first resonant frequency RF #1 (such as correspondingto operation of the resonant power converter 150 at a first resonantfrequency value) of the resonant power converter 150, the resonant powerconverter 150 provides gain as indicated by gain function 510 overdifferent magnitudes of the input voltage 120.

For a second resonant frequency setting RF #2 (such as corresponding tooperation of the resonant power converter 150 at a second resonantfrequency value) of the resonant power converter 150, the resonant powerconverter 150 provides gain as indicated by gain function 520 overdifferent magnitudes of the input voltage 120.

For a third resonant frequency setting RF #3 (such as corresponding tooperation of the resonant power converter 150 at a second resonantfrequency value) of the resonant power converter 150, the resonant powerconverter 150 provides gain as indicated by gain function 530 overdifferent magnitudes of the input voltage 120.

As previously discussed, the resonant frequency of the resonant powerconverter 150 can be adjusted via adjusting settings of the resonantcircuit 250. For example, via control signal 106 (one or more controlsignals), adjustment of the resonant frequency of the resonant powerconverter 150 can include any suitable technique such as one or more ofthe following: adjusting a magnitude of capacitance provided by resonantcapacitor component (such as capacitor Cr) associated with the resonantcircuit 250, adjusting a magnitude of inductance provided by theresonant inductor component (such as inductor Lr) associated with theresonant circuit 250, etc.

Adjusting the magnitude of the capacitance (Cr) associated with theresonant power converter 150 can include selectively coupling a numberof capacitors in parallel.

As further shown, the graph 500 illustrates how the gain provided by theresonant power converter 150 changes based on different settings of theswitching frequency Fsw used by the controller 140 to produce thecontrol signals 105 driving gates of respective switches S1 and S2.

FIG. 6 is an example graph illustrating operation of a resonant powerconverter over a range of different magnitudes of input voltageaccording to embodiments herein.

As previously discussed, the input voltage range such as between 40 VDCand 60 VDC can be split up into multiple ranges including range #1,range #2, and range #3.

Each input voltage range is assigned a different resonant frequencysetting. For example, the first input voltage range #1 is assigned afirst resonant frequency setting RF setting #1; the second input voltagerange #2 is assigned a second resonant frequency setting RF setting #2;the third input voltage range #3 is assigned a third resonant frequencysetting RF setting #3.

The controller 140 uses each of the resonant frequency settingsassociated with the different ranges and the switching frequency Fsw tocontrol operation of the resonant power converter 150. In suchembodiments, a gain of the resonant power converter 150 is a piece-wisegain function including a combination of: i) a first gain function suchas a portion of gain function 510 in range #1, ii) a second gainfunction such as a portion of gain function 520 in range #2, and iii) athird gain function such as a portion of gain function 530 in range #3.

In this example embodiment, the piece-wise gain function 620 in graph600 illustrates how the magnitude of the first gain function 510 and amagnitude of the second gain function 520 is substantially equal at atransition frequency F1 between the first input voltage range (range #1)and the second input voltage range (range #2). Additionally, themagnitude of the second gain function 510 and a magnitude of the thirdgain function 530 is substantially equal at a transition frequency F2between the second input voltage range (range #2) and the third inputvoltage range (range #3). As previously discussed, embodiments hereininclude implementing hysteresis when transition from using one gainfunction to the next. For example, when operating in range 2, thecontroller does not switchover to using range #1 until the input voltageis less than a threshold value F1. After operating in range #1, thecontroller does not switchover to operating in the range #2 again untilthe input voltage is greater than the threshold value plus an offsetvalue.

Note that, fundamentally, a piece-wise defined gain function as shown inFIG. 6 is compatible both with a full regulation approach and with asemi-regulated approach as shown in FIG. 3. Embodiments herein caninclude full regulation with piece-wise adjustable gain function andsemi-regulated approach with or without piece-wise adjusted gainfunction.

FIG. 7 an example diagram illustrating of map information used tocontrol operation of a resonant power converter according to embodimentsherein.

Map information 138 indicates settings of the resonant power converter150 for each of different input voltage magnitudes. For example, inaccordance with the piece-wise function 620, map information 138indicates to: i) set the resonant frequency of the resonant circuit 250to resonant frequency setting #1 for instances in which the magnitude ofthe input voltage 120 falls within the first input voltage range #1(between 38 VDC and 45 VDC), ii) set the resonant frequency of theresonant circuit 250 to resonant frequency setting #2 for instances inwhich the magnitude of the input voltage 120 falls within the secondinput voltage range #2 (between 45 VDC and 53 VDC), and iii) set theresonant frequency of the resonant circuit 250 to resonant frequencysetting #3 for instances in which the magnitude of the input voltage 120falls within the third input voltage range #3 (between 53 VDC and 65VDC).

As previously discussed, via control signal 106 outputted from thecontroller 140 (FIG. 2), setting of the resonant frequency associatedwith the resonant circuit 250 can include controlling settings of anysuitable components in the resonant circuit 250.

As further shown, the map information 138 provides, for each inputvoltage range, a mapping of a magnitude of the input voltage to acorresponding switching frequency setting to be applied to the controlsignals 105 so that the resonant power converter 150 providesappropriate gain to convert the input voltage 120 to the output voltage123.

More specifically, referring again to FIG. 2, during operation, thecontroller 140 determines a voltage range (of the multiple voltageranges) in which the magnitude of the input voltage resides and appliesan appropriate resonant frequency setting.

Assume that the monitor resource 141 detects that the magnitude of theinput voltage is 40 VDC. In such an instance, the controller 140 detectsthat 40 VDC falls within the first range #1. The controller 140 thenapplies the corresponding resonant frequency setting #1 (RF 1)associated with range #1 to the resonant circuit 250. The controller 140further maps 40 VDC to a switching frequency of 0.62×RF 1 (where RF isassociated with range #1) and applies this switching frequency to thecontrol signals 105.

As previously discussed, the magnitude of the input voltage 120 changesover time. Assume that the monitor resource 141 detects that themagnitude of the input voltage is 48 VDC. In such an instance, thecontroller 140 detects that 48 VDC falls within the first range #2. Thecontroller 140 then applies the corresponding resonant frequency setting#2 (RF 2) associated with range #2 to the resonant circuit 250. Thecontroller 140 further maps 48 VDC to a switching frequency of 1.0×RF 2and applies this switching frequency to the control signals 105. In oneembodiment, this is a point of optimal conversion efficiency associatedwith conversion of the input voltage 120 to the output voltage 123.

Sometime later, assume that the monitor resource 141 detects that themagnitude of the input voltage is 56 VDC. In such an instance, thecontroller 140 detects that 56 VDC falls within the range #3. Thecontroller 140 then applies the corresponding resonant frequency setting#3 (RF 3) associated with range #3 to the resonant circuit 250. Thecontroller 140 further maps 56 VDC to a switching frequency of 1.32×RF 3and applies this switching frequency to the control signals 105.

As previously discussed, operating in range #1 and range #3 may provideless efficient conversion than operating in the range #2. However, theoperation in range #1 and range #3 provides appropriate gain such that amagnitude of the output voltage 123 is maintained closer to a desiredtarget value such as 6 VDC.

Note that embodiments herein as described in FIGS. 5 and 6 can beconsidered independent ideas, which may be implemented separately.

FIG. 8 is an example diagram illustrating adjustment of a switchingfrequency and/or a gain of a resonant power converter according toembodiments herein.

According to further embodiments herein, the controller 140 can beconfigured to change either the resonant frequency associated with theresonant circuit 250 or switching frequency Fsw to control the operationof the resonant power converter 150.

For example, assume that the controller 140 initially operates theresonant power converter at a resonant frequency setting #2 andswitching frequency of around 150 KHz as indicated by the operatingpoint A in graph 800. In such an instance, to change the gain associatedwith the resonant power converter 150, the controller 140 adjusts theresonant frequency of the resonant power converter 150 from gainfunction 520 to gain function 510 (associated with resonant frequencysetting #1) as indicated by the operating point A′ while the switchingfrequency is set to a fixed value such as 150 KHz.

Accordingly, while a magnitude of the switching frequency is set to afixed value such as 150 KHz, the controller 140 can be configured tovary a magnitude of the resonant frequency of the resonant powerconverter 150 (such as from resonant frequency setting #2 to resonantfrequency setting #1 or other suitable settings) to control a respectivegain of the resonant power converter 150 and conversion of the inputvoltage 120 to the output voltage 123.

As another example, assume that the controller 140 initially operatesthe resonant power converter at a resonant frequency setting #2(associated with gain function 520) and switching frequency of around182 KHz as indicated by the operating point B. In such an instance, tomaintain the gain associated with the resonant power converter 150 to befixed, as indicated by the operating point B′(gain function 510), thecontroller 140: i) adjusts the resonant frequency of the resonant powerconverter 150 to resonant frequency setting #1, and ii) adjusts theswitching frequency from 182 KHz to 115 KHz.

Accordingly, embodiments herein include modifying both the resonantfrequency of the resonant circuit 250 and a switching frequency Fsw ofthe resonant power converter 150 to maintain the gain at a constantvalue.

FIG. 9 is an example diagram illustrating adjustment of a normalizedswitching frequency and/or a gain of a resonant power converteraccording to embodiments herein.

As previously discussed, the resonant frequency and/or switchingfrequency associated with the resonant power converter 150 can bechanged to control operation of the power system 100 and conversion ofthe input voltage 120 to the output voltage 123.

FIG. 10 is an example diagram illustrating example computer architectureoperable to execute one or more methods according to embodiments herein.

As previously discussed, any of the resources (such as controller 140,etc.) as discussed herein can be configured to include computerprocessor hardware and/or corresponding executable instructions to carryout the different operations as discussed herein.

As shown, computer system 1000 of the present example includes aninterconnect 1011 that couples computer readable storage media 1012 suchas a non-transitory type of media (which can be any suitable type ofhardware storage medium in which digital information can be stored andretrieved), a processor 1013 (computer processor hardware), I/Ointerface 1014, and a communications interface 1017.

I/O interface(s) 1014 supports connectivity to external hardware 1099such as a keyboard, display screen, repository, etc.

Computer readable storage medium 1012 can be any hardware storage devicesuch as memory, optical storage, hard drive, floppy disk, etc. In oneembodiment, the computer readable storage medium 1012 storesinstructions and/or data.

As shown, computer readable storage media 1012 can be encoded withcontroller/monitor application 140-1 (e.g., including instructions) tocarry out any of the operations as discussed herein.

During operation of one embodiment, processor 1013 accesses computerreadable storage media 1012 via the use of interconnect 1011 in order tolaunch, run, execute, interpret or otherwise perform the instructions incontroller/monitor application 140-1 stored on computer readable storagemedium 1012. Execution of the controller/monitor application 140-1produces controller/monitor process 140-2 to carry out any of theoperations and/or processes as discussed herein.

Those skilled in the art will understand that the computer system 1000can include other processes and/or software and hardware components,such as an operating system that controls allocation and use of hardwareresources to execute controller/monitor application 140-1.

In accordance with different embodiments, note that computer system mayreside in any of various types of devices, including, but not limitedto, a power supply, switched-capacitor converter, resonant powerconverter, a mobile computer, a personal computer system, a wirelessdevice, a wireless access point, a base station, phone device, desktopcomputer, laptop, notebook, netbook computer, mainframe computer system,handheld computer, workstation, network computer, application server,storage device, a consumer electronics device such as a camera,camcorder, set top box, mobile device, video game console, handheldvideo game device, a peripheral device such as a switch, modem, router,set-top box, content management device, handheld remote control device,any type of computing or electronic device, etc. The computer system1050 may reside at any location or can be included in any suitableresource in any network environment to implement functionality asdiscussed herein.

Functionality supported by one or more resources as described herein arediscussed via flowchart in FIGS. 11 and 12. Note that the steps in theflowcharts below can be executed in any suitable order.

FIG. 11 is a flowchart 1100 illustrating an example method according toembodiments herein. Note that there will be some overlap with respect toconcepts as discussed above.

In processing operation 1110, the monitor resource 141 monitors amagnitude of an input voltage 120 supplied to a resonant power converter150.

In processing operation 1120, the controller 140 dynamically controls arespective gain of the resonant power converter 150 depending on amagnitude of the input voltage 120.

In processing operation 1130, the controller 140 controls switches S1and S2 in the resonant power converter 150 resulting in conversion ofthe input voltage 120 into an output voltage 120.

FIG. 12 is a flowchart 1200 illustrating an example method according toembodiments herein. Note that there will be some overlap with respect toconcepts as discussed above.

In processing operation 1210, the monitor resource 141 monitors amagnitude of an input voltage 120 supplied to a power converter 150.

In processing operation 1220, the controller 140 sets a resonancefrequency of the power converter 150 depending on a magnitude of theinput voltage 120.

In processing operation 1230, the controller dynamically controls aswitching frequency Fsw of switches S1 and S2 in the power converter 150depending on a magnitude of the input voltage 120. The power converterconverts the input voltage 120 into an output voltage 123.

FIG. 13 is an example diagram illustrating fabrication of a circuitboard according to embodiments herein.

In this example embodiment, fabricator 1340: receives a substrate 1310(such as a circuit board); affixes the power system 100 (such as a powersupply and corresponding components) to the substrate 1310.

The fabricator 1340 further affixes the power converter 195 to thesubstrate 1310. Via circuit path 1321 (such as one or more traces,etc.), the fabricator 1340 couples the power system 100 to the powerconverter 195. Via circuit path 1322 (such as one or more traces, etc.),the fabricator 1340 couples the power converter 195 to a load 1318. Inone embodiment, the circuit path 1321 conveys output voltage 123generated from the power supply 100 to the power converter 195. Thepower converter 195 converts the received output voltage 123 into atarget voltage that drives load 1318.

Accordingly, embodiments herein include a system comprising: a substrate1310 (such as a circuit board, standalone board, mother board,standalone board destined to be coupled to a mother board, etc.); apower system 100 including a resonant power converter 150 as describedherein; and a load 1318, the load 118 powered based on energy or powerprovided by the output voltage 123. For example, the power converterconverts the output voltage 123 into a suitable secondary output voltagethat powers load 1318. The load 1318 can be any suitable circuit orhardware such as one or more CPUs (Central Processing Units), GPUs(Graphics Processing Unit) and ASICs (Application Specific IntegratedCircuits such those including one or more Artificial IntelligenceAccelerators), which can be located on the substrate 1310.

FIG. 14 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode without changing a resonantfrequency according to embodiments herein.

As shown in graph 1410, embodiments herein include implementing a singlegain function 1421 (G=Gain) to provide semi regulation without changingthe resonant frequency of the resonant power converter 150 based on theinput voltage 120. As shown in graph 1410, the controller 140 adjuststhe switching frequency (Fsw) associated with switching of switches S1and S2 to adjust a gain of the resonant power converter 150 fordifferent magnitudes of the input voltage 120.

FIG. 15 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode without changing a resonantfrequency but with optimized resonant tank circuit according toembodiments herein.

In contrast to previous FIG. 14, FIG. 15 shows an optimized resonanttank with a flatter gain curve. Such an optimization reduces the amountof resonant current in the tank and increases the efficiency of theconverter.

As shown in graph 1510, embodiments herein include implementing a singlegain function 1521 (optimized for input voltages between 40 and 60 VDC,G=Gain) to provide semi regulation without changing the resonantfrequency of the resonant power converter 150 based on the input voltage120. As shown in graph 1510, the controller 140 adjusts the switchingfrequency (Fsw) associated with switching of switches S1 and S2 toadjust a gain of the resonant power converter 150 for differentmagnitudes of the input voltage 120.

FIG. 16 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode with changes to a resonant frequencyaccording to embodiments herein.

As shown in graph 1610, in a manner as previously discussed, embodimentsherein include implementing different gain functions (G=Gain) over arange of different input voltages. For example, when the magnitude ofthe input voltage 120 is less than a threshold value Vinth1 (such aswhen the input voltage falls in a first range), the controller 140 setsthe resonant frequency of the resonant power converter 150 to a valueassociated with gain function 1621; when the magnitude of the inputvoltage 120 is between threshold value Vinth1 and Vinth2 (such as whenthe input voltage falls in a second range), the controller 140 sets theresonant frequency of the resonant power converter 150 to a valueassociated with gain function 1622; when the magnitude of the inputvoltage 120 is greater than threshold value Vinth2 (such as when theinput voltage falls in a third range), the controller 140 sets theresonant frequency of the resonant power converter 150 to a valueassociated with gain function 1623. In each of the different ranges, ina manner as previously discussed, the controller 150 adjusts theswitching frequency Fsw and implements hysteresis as the input voltagechanges over time.

FIG. 17 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode with changes to a resonant frequencybut with optimized resonant tank circuit according to embodimentsherein.

In contrast to previous FIG. 16, FIG. 17 shows an optimized resonanttank with a flatter gain curve. Such an optimization reduces the amountof resonant current in the tank and increases the efficiency of theconverter.

As shown in graph 1710, in a manner as previously discussed, embodimentsherein include implementing different optimized gain functions (G=Gain)over a range of different input voltages. For example, when themagnitude of the input voltage 120 is less than a threshold value Vinth1(such as when the input voltage falls in a first range), the controller140 sets the resonant frequency of the resonant power converter 150 to avalue associated with gain function 1721; when the magnitude of theinput voltage 120 is between threshold value Vinth1 and Vinth2 (such aswhen the input voltage falls in a second range), the controller 140 setsthe resonant frequency of the resonant power converter 150 to a valueassociated with gain function 1722; when the magnitude of the inputvoltage 120 is greater than threshold value Vinth2 (such as when theinput voltage falls in a third range), the controller 140 sets theresonant frequency of the resonant power converter 150 to a valueassociated with gain function 1723. In each of the different ranges, ina manner as previously discussed, the controller 150 adjusts theswitching frequency Fsw and implements hysteresis as the input voltagechanges over time.

Embodiments herein further include a power conversion system operativeto receive a fixed or narrow range input voltage. A resonant powerconverter produces a wide range of varying output voltages. Suchapplications include but are not limited to, for example, chargingbatteries for electric vehicles in which the output voltage used tocharge the batteries varies.

In one embodiment, the power converter as discussed herein monitors theoutput voltage and/or a ratio of an output voltage to input voltageinstead of merely monitoring the input voltage. In case ofsemi-regulating power conversion, there is now a pre-regulatingconverter disposed in a circuit before an isolating converter instead ofthe post-regulating converter of the prior embodiments above. Apre-regulating converter as discussed herein, such as is in the contextof battery charging, e.g., a power factor correction converter with avariable DC link voltage.

FIG. 18 is an example diagram illustrating a power supply including aresonant power converter and corresponding controller according toembodiments herein.

As shown in this example embodiment, the power system 1000 (i.e., powersupply) includes controller 1400 and resonant power converter 1500. Inone embodiment, the power system 1000 receives an input voltage 1200 andproduces an output voltage 1230.

In one embodiment, the power supply 1510 (such as a power converter) isa pre-regulating power converter providing the input voltage 1200 at afixed voltage value or a voltage that varies within a narrow band inputvoltage range.

Note that embodiments herein can include piece-wise adjusting of theresonance frequency of the resonant power converter 1500 depending on amagnitude of the output voltage 1230 and/or a magnitude of the inputvoltage 1200, providing full regulation within each of the outputvoltage/input voltage regions. Embodiments herein include supplying theoutput voltage 1230 directly to any kind of circuit such as a load.

Note further that the resonant power converter 1500 can be any suitabletype of power converter. For example, the power converter as describedherein can be implemented in accordance with any isolated ornon-isolated technology.

Examples of isolated power converter topologies include hard switchinghalf bridge converters, LLC converters, phase shift ZVS (Zero VoltageSwitching) converters, etc.

Examples of non-isolated topologies include buck converters, switchedcapacitor converters, tapped inductor switched tank converters,combination converters such as buck/switched capacitor converters, etc.

In further example embodiments, the resonant power converter 1500 is asemi-regulated bus converter or other suitable entity operative toconvert the input voltage 1200 into the output voltage 1230. In such aninstance, the amount and/or mode of voltage regulation provided by thecontroller 1400 varies depending on a magnitude of the output voltage1230 and/or input voltage 1200. Note that further embodiments herein caninclude providing full regulation via a piece-wise set resonancefrequency bands.

Note further that, in one embodiment, the controller 1400 furtherincludes monitor resource 1410 and corresponding map information 1380.During operation, as previously discussed, the resonant power converter1500 receives an input voltage 1200 and converts it into an outputvoltage 1230. As its name suggests, the monitor resource 1410 monitors amagnitude of the output voltage 1230 and/or the input voltage 1200.Depending on a magnitude of the output voltage 1230 and/or the inputvoltage 1200 (such as Vin1), the controller 1400 controls a respectiveone or more parameters such as gain provided by the resonant powerconverter 1500.

Thus, embodiments herein include adjusting a gain provided by theresonant power converter 1500 depending on a magnitude of the outputvoltage 1230 (a.k.a., Vout1) and/or input voltage 1200 as monitored bythe monitor resource 1400.

In one embodiment, the gain associated with the resonant power converter1500 determines the voltage conversion ratio of the resonant powerconverter 1500.

For example, the output voltage 1230 (i.e., Vout1),Vout1=Vin*Ns1/Np1*Gain1,

where Vin is the input voltage 1200, Ns1=number of turns of thesecondary winding associated with the transformer T11, Np1=number ofturns on the primary winding associated with the transformer T11, Gain1is the gain provided by the resonant power converter 1500.Gain1=(Vout1/Vin)*(Np1/Ns1),

or more generally, Gain1=(Vout1/Vin)*Scale-Factor, where the scalefactor is any suitable value chosen to convert an input voltage 1200 toa respective output voltage 1230 in a desired output voltage range.

Adjusting the gain (such as Vin1 times some scale factor) associatedwith the resonant power converter 1500 provides more efficientconversion of the input voltage 1200 to an output voltage 1230 forvarying input voltage settings. In one embodiment, embodiments hereininclude operating the resonant power converter 1500 as close as possibleto a gain of around 1 to maximize efficiency.

More specifically, assume that for a majority of time, the resonantpower converter 1500 receives an input voltage 1200 that is close invalue (such as within 5% of point) to an expected average value such as400 VDC. In such an instance, conversion efficiency is very high. Asfurther discussed herein, embodiments herein include controlling theresonant power converter 1500 to operate in a highly efficient low gainmode during conditions when the desired output voltage 1230 resides in anormal voltage range such as between 407 VDC and 430 VDC. When amagnitude of the output voltage falls outside this normal range (such aswhen the output voltage 1200 is greater than 430 VDC or less than 400VDC), the output voltage 1230 would deviate if the resonant powerconverter were operated in the most efficient gain mode close to a gainof 1 associated with the normal voltage range as previously discussed.

In accordance with embodiments herein, although less efficient, in orderprovide better regulation of the output voltage 1230 (such as an outputvoltage closer to a desired target value without providing fullregulation, which is less efficient), the controller 1400 operates theresonant power converter 1500 in a non-unity gain mode (where the gainis substantially higher than one or substantially lower than one whenthe output voltage 1230 falls outside the normal range to maintain themagnitude of the output voltage 1230 within a desired range. Furtherdetails are discussed below.

Note that the controller 1400 can be configured to control any suitableone or more control parameters of the resonant power converter 1500 tomaintain the magnitude of the output voltage 1230 within a desiredrange. The power system 1000 supplies the output voltage 1230 to anysuitable circuit 1960 such as load, power converter, etc., which furtherconverts the output voltage 1230 into a highly regulated supply voltagethat powers a load. In one embodiment, the output voltage 1230 is usedto power a circuit 1960 such as to charge a battery.

In one embodiment, depending on the magnitude of the output voltage1230, the controller 1400 dynamically controls parameters such as: i) aswitching frequency Fsw1 of switches in the resonant power converter,ii) a resonant frequency of the resonant power converter 1500, etc.

Dynamic control of the switching frequency and/or the resonant frequencyoperation associated with the resonant power converter 1500 maintains amagnitude of the output voltage 1230 within a desired voltage range,closer to a desired target DC voltage value.

Note further that embodiments herein optionally include producing mapinformation 1380. When implemented, the map information 1380 provides amapping between the magnitude of the input voltage 1200 and a setting ofthe switching frequency applied to one or more switches in the resonantpower converter 1500. Thus, via the map information 1380, as furtherdiscussed herein, the controller 1400 maps a desired magnitude of theoutput voltage 1230 to a resonant frequency value and sets the resonantfrequency operation of the resonant power converter 1500 to the resonantfrequency value.

Additionally, or alternatively, the controller 1400 maps the currentmagnitude of the desired output voltage 1230 to an appropriate switchingfrequency value, Fsw1. The controller 140 then sets the switchingfrequency of the resonant power converter 1500 to that switchingfrequency value, Fsw1.

FIG. 19 is an example diagram illustrating details of a resonant powerconverter and a corresponding controller according to embodimentsherein.

As shown, the power system 1000 includes controller 1400, input voltagesource Vin1, switches S11 and S12, capacitor Cr1, inductor Lr1,transformer T11 (such as a tapped-transformer), diode D11, diode D12,capacitor Co1, and resistor R1.

As previously discussed, the controller 1400 includes monitor resource1410 and map information 1380.

Further in this example embodiment, as shown, the switches S11 and S12are coupled in series between the input voltage source Vin1 andcorresponding ground reference. For example, the drain node (D) of theswitch S11 is coupled to the input voltage source Vin1. At node 2810,the source node (S) of switch S11 is coupled to the drain node (D) ofswitch S12 as well as a corresponding node of capacitor Cr1.

The source node (S) of switch S12 is coupled to the ground referencevoltage.

The controller 1400 is coupled to supply the control signal 1050-1 tothe gate node (G) of switch S11; the controller 1400 is coupled tosupply the control signal 1050-2 to the gate node (G) of switch S12.

As further shown, resonant circuit 2500 such as the combination of thecapacitor Cr1, inductor Lr1, and primary winding 2610 of the transformerT11 are connected in series between node 2810 and ground. Inductor Lm1represents the magnetizing inductance associated with the primarywinding 2610 of transformer T11.

The primary winding of T11 is magnetically coupled to both secondarywinding 2620-1 and secondary winding 2620-2. If desired, node 2920 (suchas tap associated with the transformer T11) can be connected to ground.Each of the primary winding 2610 and secondary windings 2620 can includeany suitable number of turns. In one nonlimiting example embodiment, thewindings include an appropriate number of turns such that the resonantpower converter 1500 converts, on average, an input voltage 123 of 400VDC (or other suitable magnitude) into an output voltage 1230 of between350-525 VDC or other suitable value, although the resonant powerconverter 1500 can be configured to provide any suitable voltageconversion.

Yet further, diode D11 is connected between the node 2910 of thetransformer T11 and the output voltage node 2830. Diode D12 is connectedbetween the node 2930 of the transformer T11 and the output voltage node2830.

Finally, capacitor Co1 is coupled between the output voltage node 2830in the node 2920. Resistor R1 is connected between the output voltagenode 2830 and the node 2920.

Thus, in this example embodiment shown, the resonant power converter 150includes a first switch S11 and a second switch S12.

During operation, the controller 1400 controls switching of the firstswitch S11 to selectively apply a first voltage (such as the inputvoltage 1200) to an input (node 2810) of the resonant circuit 2500 ofthe resonant power converter 1500; the controller 1400 controlsswitching of the second switch S12 to selectively apply a second voltage(such as a ground reference voltage with respect to the input voltage)to the input (node 2810) of the resonant circuit 2500 of the resonantpower converter circuit 1500.

In accordance with further embodiments, switching of the switches S11and S12 during each of multiple control cycles includes a first switchsetting of activating the switch S11 (providing a low resistive pathbetween respective source and drain nodes) for a duration of time whileswitch S12 is deactivated (providing a high resistive path). Switchingof the switches S11 and S12 during each of multiple control cyclesfurther includes a second switch setting such as activating the switchS12 (providing a low resistive path between respective source and drainnodes) for a duration of time while switch S11 is deactivated (providinga high resistive path). The controller 1400 repeatedly switches betweenthe first switch setting and the second switch setting to convert theinput voltage 1200 into the output voltage 1230.

As previously discussed, the map information 1380 provides a mappingbetween the magnitude of the output voltage 1230 and a setting of theresonant frequency associated with operating the resonant powerconverter 1500. Thus, via the map information 1380, the controller 1400maps the current magnitude of the output voltage 1230 to a resonantfrequency value and sets the resonant frequency operation of theresonant power converter 1500 (specifically resonant circuit 2500) tothe selected resonant frequency value.

In one embodiment, control or setting of the resonant frequencyassociated with the resonant circuit 2500 can be achieved in anysuitable manner. For example, any of one or more components capacitorCr1, inductor Lr1, and inductor Lm1 can be adjusted to change a resonantfrequency of the resonant circuit 2500.

Additionally, or alternatively, as further discussed herein, thecontroller 1400 maps the current magnitude of the output voltage 1230 toa switching frequency value, Fsw1, associated with controlling switchesS11 and S12. For example, the controller 1400 sets the switchingfrequency (Fsw1) of producing the control signals 1050-1 and 1050-2 ofthe resonant power converter 1200 to the selected switching frequencyvalue (Fsw1).

Again, in one embodiment, the gain associated with the resonant powerconverter 1500 determines the voltage conversion ratio of the LLC(together with the transformer T11 turn ratio).

For example, the output voltage 1230 (i.e., Vout1),Vout1=Vin1*Ns1/Np1*Gain1,

where Vin1 is the input voltage 1200, Ns1=number of turns of thesecondary winding associated with the transformer T11, Np1=number ofturns on the primary winding associated with the transformer T11, Gain1is the gain provided by the resonant power converter 1500.Gain1=(Vout1/Vin1)*(Np1/Ns1)

FIG. 20 is an example graph illustrating operation of a resonant powerconverter over a range of different magnitudes of input voltageaccording to embodiments herein.

Assume in this example embodiment that the transformer T11 is configuredwith a winding ratio of primary winding: secondary winding being 1:1.

In one embodiment, note that the resonant power converter 1500 operatesin a semi-regulating manner. The resonant power converter 1500 receivesan input voltage 1200 falling within a narrow range input voltage band.In graph 3000, based on an input voltage 1200 between 380V to 460V, theresonant power converter produces a wide output voltage ranging from350V to 525V. In one embodiment, a fixed regulated converter receives inthis example, a fixed voltage of 420V to produce the same output voltagerange (350-525). In one nonlimiting example embodiment, the resonantpower converter as discussed herein operates far away from its resonancefrequency and therefore operates at a less efficient operation point.

Note further that a non-regulating resonant power converter would (suchas transformer ratio 1:1) require an input voltage band of 350V to 525Vto produce the above mentioned band of output voltage to follow thebattery voltage depending on state-of-charge. A pre-regulating convertersuch as a Power factor correction stage would have difficulties toregulate to 350V as this voltage is too close to the peak of an AC inputvoltage at 230V. Furthermore, the power factor correction stage wouldneed power semiconductor devices rated at a higher voltage class than650V in order to be able to regulate to 525V. Also, the subsequent powerconverter would need e.g. 800V rated power semiconductors. Such a systemwould have therefore a higher system cost.

Conventional techniques include implementation of function 3100 orfunction 3300 to generate a respective output voltage 1230. For example,when the conventional power converter function 3300 (full regulation) isimplemented to convert an input voltage 1200 into an output voltage1230, the output voltage 1230 is a constant target voltage (such as 400VDC) regardless of a magnitude of the input voltage 1200. When thefunction 3100 (fully unregulated mode) is implemented to convert aninput voltage 1200 into an output voltage 1230, the output voltage 1230linearly varies depending on a magnitude of the input voltage 1200.

As further discussed herein, in contrast to conventional techniques, thecontroller 1400 is operative to provide semi-regulated control (mode3200) of converting the input voltage 1200 into the output voltage 1230,the semi-regulated control operated between a fully unregulatedoperational mode (3100) and a fully regulated operational mode (3300).

Embodiments herein include implementation of an advanced transferfunction 3200 (semi-regulated output) as shown in graph 3000. In thiscase, the resonant power converter would provide little to no regulationin a central band 3500 of output voltage values, while providingsemi-regulation both at the upper end (such as output voltages greaterthan band 3500) and lower end (such as output voltages less than band3500) of the full output voltage range between 350 and 525 VDC. In thiscase, operation of a power converter 1500 as described herein in band3500 provides high efficiency, which is operation for a majority of timein which the resonant power converter 1500 converts the input voltage1200 into the output voltage 1230. Operation outside the band 3500 isslightly less efficient, providing better regulation of the outputvoltage 1230 than does the fully unregulated function 3100.

Accordingly, embodiments herein include providing varying degrees ofregulation depending on a magnitude of the output voltage 1230 and whichof multiple different output voltage ranges the magnitude falls. In oneembodiment, the term degrees of regulation means how fast gain isadjusted as a function of varying output voltage, if the output voltagehappens to vary.

FIG. 21 is an example graph illustrating operation of a resonant powerconverter over a range of different magnitudes of input voltageaccording to embodiments herein.

Graph 4000 illustrates example gain 4200 associated with the resonantpower converter 1500 over a range of different output voltage valuessuch as between 350 VDC and 525 VDC. As shown, gain 4200 falls betweengain 4100 associated with a fully unregulated power converter and gain4300 associated with a fully regulated power converter.

FIG. 22 is an example graph illustrating operation of a resonant powerconverter over a range of different magnitudes of output voltageaccording to embodiments herein.

Further embodiments herein include splitting the input voltage range(such as between 350 VDC and 525 VDC) associated with the resonant powerconverter 1500 into any number of ranges. In this example embodiment,the output voltage range associated with the resonant power converter1500 is split into multiple ranges such as range #11, range #12, range#13.

Yet further embodiments herein include assigning each of the multiplevoltage ranges a different resonant frequency setting. In such aninstance, the resonant power converter 1500 provides a different gainfunction when converting the input voltage 1200 into an output voltage1230.

Note that embodiments herein include not only adjusting the resonantfrequency setting. For example, embodiments herein include adjusting thegain function as shown in FIG. 22. This typically includes changing theratio of Lr1/Lm1 of the resonant power converter. In one embodiment,there are three different operating ranges with distinctly differentgain functions.

For example, for a first resonant frequency RF #11 (such ascorresponding to operation of the resonant power converter 1500 at afirst resonant frequency value) of the resonant power converter 1500,the resonant power converter 1500 provides gain as indicated by gainfunction 5100 over different magnitudes of the output voltage 1230.

For a second resonant frequency setting RF #12 (such as corresponding tooperation of the resonant power converter 1500 at a second resonantfrequency value) of the resonant power converter 1500, the resonantpower converter 1500 provides gain as indicated by gain function 5200over different magnitudes of the output voltage 1230.

For a third resonant frequency setting RF #13 (such as corresponding tooperation of the resonant power converter 1500 at a third resonantfrequency value) of the resonant power converter 1500, the resonantpower converter 1500 provides gain as indicated by gain function 5300over different magnitudes of the output voltage 1230.

As previously discussed, the resonant frequency of the resonant powerconverter 1500 can be adjusted via adjusting settings of the resonantcircuit 2500. For example, via control signal 1060 (one or more controlsignals), adjustment of the resonant frequency of the resonant powerconverter 1500 can include any suitable technique such as one or more ofthe following: adjusting a magnitude of capacitance provided by resonantcapacitor component (such as capacitor Cr1) associated with the resonantcircuit 2500 associated with the resonant power converter 1500,adjusting a magnitude of inductance provided by the resonant inductorcomponent (such as inductor Lr1) associated with the resonant circuit2500, etc.

Adjusting the magnitude of the capacitance (Cr1) associated with theresonant power converter 1500 can include selectively coupling a numberof capacitors in parallel.

As further shown, the graph 5000 illustrates how the gain provided bythe resonant power converter 1500 changes based on different settings ofthe switching frequency Fsw1 used by the controller 1400 to produce thecontrol signals 1050 driving gates of respective switches S11 and S12.

FIG. 23 is an example graph illustrating operation of a resonant powerconverter over a range of different magnitudes of output voltageaccording to embodiments herein.

As previously discussed, the output voltage range such as between 350VDC and 525 VDC can be split up into multiple ranges including range#11, range #12, and range #13.

Each output voltage range is assigned a different resonant frequencysetting. For example, the first output voltage range #11 is assigned afirst resonant frequency setting RF setting #11 of resonant powerconverter 1500; the second output voltage range #12 is assigned a secondresonant frequency setting RF setting #12 of resonant power converter1500; the third output voltage range #13 is assigned a third resonantfrequency setting RF setting #13 of resonant power converter 1500.

The controller 1400 uses each of the resonant frequency settingsassociated with the different ranges and the switching frequency Fsw1 tocontrol operation of the resonant power converter 1500. In suchembodiments, a gain of the resonant power converter 1500 is a piece-wisegain function 6200 including a combination of: i) a first gain functionsuch as a portion of gain function 5100 in range #11, ii) a second gainfunction such as a portion of gain function 5200 in range #12, and iii)a third gain function such as a portion of gain function 5300 in range#13.

In this example embodiment, the piece-wise gain function 6200 in graph6000 illustrates how the magnitude of the first gain function 5100 and amagnitude of the second gain function 5200 is substantially equal at atransition frequency F11 between the first output voltage range (range#11) and the second output voltage range (range #12). Additionally, themagnitude of the second gain function 5100 and a magnitude of the thirdgain function 5300 is substantially equal at a transition frequency F12between the second output voltage range (range #12) and the third outputvoltage range (range #13).

As previously discussed, embodiments herein include implementinghysteresis when transition from using one gain function to the next. Forexample, when operating in range #12, the controller 1400 does notswitchover to using range #11 until the output voltage is less than athreshold value F11. After operating in range #11, the controller doesnot switchover to operating in the range #12 again until the outputvoltage is greater than the threshold value plus an offset value.

Note that, fundamentally, a piece-wise defined gain function as shown inFIG. 23 is compatible both with a full regulation approach and with asemi-regulated approach as shown in FIG. 20. Embodiments herein caninclude full regulation with piece-wise adjustable gain function andsemi-regulated approach with or without piece-wise adjusted gainfunction.

FIG. 24 is an example diagram illustrating map information used tocontrol operation of a resonant power converter according to embodimentsherein.

Map information 1380 indicates settings of the resonant power converter1500 for each of different output voltage magnitudes. For example, inaccordance with the piece-wise function 6200, map information 1380indicates to: i) set the resonant frequency of the resonant circuit 2500to resonant frequency setting #11 (RF 11) for instances in which themagnitude of the output voltage 1230 falls within the first outputvoltage range #11 (between 430 VDC and 525 VDC), ii) set the resonantfrequency of the resonant circuit 2500 to resonant frequency setting #12for instances in which the magnitude of the output voltage 1230 fallswithin the second output voltage range #12 (between 410 VDC and 430VDC), and iii) set the resonant frequency of the resonant circuit 2500to resonant frequency setting #13 for instances in which the magnitudeof the output voltage 1230 falls within the third output voltage range#13 (between 350 VDC and 407 VDC).

As previously discussed, via control signal 1060 outputted from thecontroller 1400 (FIG. 19), setting of the resonant frequency associatedwith the resonant circuit 2500 can include controlling settings of anysuitable components (such as capacitors, windings, inductance, windings,etc.) in the resonant circuit 2500.

As further shown, the map information 1380 provides, for each outputvoltage range, a mapping of a magnitude of the output voltage to acorresponding switching frequency setting to be applied to the controlsignals 1050 so that the resonant power converter 1500 providesappropriate gain to convert the input voltage 1200 to the output voltage1230.

More specifically, referring again to FIG. 19, during operation, thecontroller 1400 determines a voltage range (of the multiple voltageranges) in which the magnitude of the output voltage 1230 resides andapplies an appropriate resonant frequency setting.

Assume that the monitor resource 1410 detects that the magnitude of theoutput voltage is 525 VDC. In such an instance, the controller 1400detects that 525 VDC falls within the first range #11. The controller1400 then applies the corresponding resonant frequency setting #11 (RF11) associated with range #11 to the resonant circuit 2500. Thecontroller 1400 further maps 525 VDC to a switching frequency of 0.47×RF11 (where RF 11 is associated with range #11) and applies this resultingswitching frequency 0.47×RF 11 to the control signals 1050.

As previously discussed, the magnitude of the output voltage 1230 maychange over time. Assume that the monitor resource 1410 detects that themagnitude of the output voltage 1230 is 425 VDC. In such an instance,the controller 1400 detects that 425 VDC falls within the second range#12. The controller 1400 then applies the corresponding resonantfrequency setting #12 (RF 12) associated with range #12 to the resonantcircuit 2500. The controller 1400 further maps 425 VDC to a switchingfrequency of 0.88×RF 12 and applies this switching frequency to thecontrol signals 1050. In one embodiment, this is a point of optimalconversion efficiency associated with conversion of the input voltage1200 to the output voltage 1230.

Sometime later, assume that the monitor resource 1410 detects that themagnitude of the output voltage is 375 VDC. In such an instance, thecontroller 1400 detects that 375 VDC falls within the range #13. Thecontroller 1400 then applies the corresponding resonant frequencysetting #13 (RF 13) associated with range #13 to the resonant circuit2500. The controller 1400 further maps 375 VDC to a switching frequencyof 1.18×RF 13 and applies this switching frequency to the controlsignals 1050.

As previously discussed, operating in range #11 and range #13 mayprovide less efficient conversion than operating in the range #12.However, the operation in range #11 and range #13 provides appropriategain such that a magnitude of the output voltage 123 is maintainedcloser to a desired target value.

Note further that the controller 1400 can be configured to control theresonant frequency and/or switching frequency of the resonant powerconverter 1500 based on a ratio of the magnitude of the output voltage1230 to a magnitude of the input voltage 1200. For example, thecontroller 1400 can be configured to receive a first value indicating amagnitude of the output voltage 1230 and a second value indicating amagnitude of the input voltage 1200. The controller produces a ratiovalue of the first value divided by the second value. The controller1400 uses the generated ratio value to identify a resonant frequencyvalue in which to set the resonant power converter 1500 and then derivea switching frequency from based on multiplying an adjustment factorassociated with the magnitude of the ratio value by the identifiedresonant frequency value.

FIG. 25 is an example diagram illustrating adjustment of a switchingfrequency and/or a gain of a resonant power converter according toembodiments herein.

According to further embodiments herein, the controller 1400 can beconfigured to change either the resonant frequency associated with theresonant circuit 2500 or switching frequency Fsw1 to control theoperation of the resonant power converter 1500.

For example, assume that the controller 1400 initially operates theresonant power converter at a resonant frequency setting #12 andswitching frequency of around 150 KHz as indicated by the operatingpoint A in graph 8000. In such an instance, to change the gainassociated with the resonant power converter 1500, the controller 1400adjusts the resonant frequency of the resonant power converter 1500 fromgain function 5200 to gain function 5100 (associated with resonantfrequency setting #11) as indicated by the operating point A′ while theswitching frequency is set to a fixed value such as 150 KHz.

Accordingly, while a magnitude of the switching frequency is set to afixed value such as 150 KHz, the controller 1400 can be configured tovary a magnitude of the resonant frequency of the resonant powerconverter 1500 (such as from resonant frequency setting #12 to resonantfrequency setting #11 or other suitable settings) to control arespective gain of the resonant power converter 1510 and conversion ofthe input voltage 1200 to the output voltage 1230.

As another example, assume that the controller 1400 initially operatesthe resonant power converter at a resonant frequency setting #12(associated with gain function 5200) and switching frequency of around182 KHz as indicated by the operating point B. In such an instance, tomaintain the gain associated with the resonant power converter 1500 tobe fixed, as indicated by the operating point B′(gain function 5100),the controller 1400: i) adjusts the resonant frequency of the resonantpower converter 1500 to resonant frequency setting #11, and ii) adjuststhe switching frequency from 182 KHz to 115 KHz.

Accordingly, embodiments herein include modifying one or both theresonant frequency of the resonant circuit 2500 and a switchingfrequency Fsw1 of the resonant power converter 1500 to maintain the gainat a constant value.

FIG. 26 is an example diagram illustrating adjustment of a normalizedswitching frequency and/or a gain of a resonant power converteraccording to embodiments herein.

As previously discussed, the resonant frequency and/or switchingfrequency associated with the resonant power converter 1500 can bechanged to control operation of the power system 1000 and conversion ofthe input voltage 1200 to the output voltage 1230.

FIG. 27 is a flowchart 2700 illustrating an example method according toembodiments herein. Note that there will be some overlap with respect toconcepts as discussed above.

In processing operation 2710, the monitor resource 1410 monitors amagnitude of the output voltage 1230 and/or input voltage 1200.

In processing operation 2720, the controller 1400 dynamically controls arespective gain of the resonant power converter 1500 depending on amagnitude of the output voltage 1230 and/or input voltage 1200.

In processing operation 1130, the controller 1400 controls switches S11and S12 in the resonant power converter 1500 resulting in conversion ofthe input voltage 1200 into the output voltage 1230.

FIG. 28 is a flowchart 2800 illustrating an example method according toembodiments herein. Note that there will be some overlap with respect toconcepts as discussed above.

In processing operation 2810, the monitor resource 141 monitors amagnitude of an output voltage 1230 and/or input voltage 1200.

In processing operation 2820, the controller 1400 sets a resonancefrequency of the power converter 1500 depending on a magnitude of theoutput voltage 1230 and/or input voltage 1200.

In processing operation 2830, the controller 1400 dynamically controls aswitching frequency Fsw1 of switches S11 and S12 in the power converter1500 depending on a magnitude of the output voltage 1230 and/or inputvoltage 1200. The power converter 1500 converts the input voltage 1200into the output voltage 1230.

FIG. 29 is a flowchart 2900 illustrating an example method according toembodiments herein. Note that there will be some overlap with respect toconcepts as discussed above.

In processing operation 2910, a monitor resource monitors a magnitude ofa voltage (input voltage, output voltage, or both) at a node of aresonant power converter.

In processing operation 2920, to set a respective gain of the resonantpower converter, the controller dynamically selects a resonant frequencyof the resonant power converter depending on the magnitude of thevoltage.

In processing operation 2930, the controller controls switching ofswitches in the resonant power converter at a switching frequency.

FIG. 30 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode without changing a resonantfrequency according to embodiments herein.

As shown in graph 3010, embodiments herein include implementing a singlegain function 3021 (G=Gain) to provide semi regulation without changingthe resonant frequency of the resonant power converter 1500 based on theoutput voltage 1230. As shown in graph 3010, the controller 1400 adjuststhe switching frequency (Fsw1) associated with switching of switches S11and S12 to adjust a gain of the resonant power converter 1500 fordifferent magnitudes of the output voltage 1230 between 350 and 525 VDCor other suitable range.

FIG. 31 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode without changing a resonantfrequency but with optimized resonant tank circuit according toembodiments herein.

In contrast to previous FIG. 30, FIG. 31 shows an optimized resonanttank with a flatter gain curve. Such an optimization reduces the amountof resonant current in the tank and increases the efficiency of theconverter.

As shown in graph 3110, embodiments herein include implementing a singlegain function 3121 (optimized for output voltages between 350 and 525VDC, G=Gain) to provide semi regulation without changing the resonantfrequency of the resonant power converter 1500 based on the inputvoltage 1200. As shown in graph 3110, the controller 1400 adjusts theswitching frequency (Fsw) associated with switching of switches S11 andS12 to adjust a gain of the resonant power converter 1500 for differentmagnitudes of the output voltage 1230.

FIG. 32 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode with changes to a resonant frequencyaccording to embodiments herein.

As shown in graph 3210, in a manner as previously discussed, embodimentsherein include implementing different gain functions (G=Gain) over arange of different output voltages. For example, when the magnitude ofthe output voltage 1230 is greater than a threshold value Voutth1 (suchas when the output voltage 1230 falls in a first range 430-525V), thecontroller 1400 sets the resonant frequency of the resonant powerconverter 1500 to a value associated with gain function 3221; when themagnitude of the output voltage 1230 is between threshold value Voutth1and Voutth2 (such as when the output voltage falls in a second range407-430V), the controller 1400 sets the resonant frequency of theresonant power converter 1500 to a value associated with gain function3222; when the magnitude of the output voltage 1230 is less thanthreshold value Voutth2 (such as when the output voltage falls in athird range 350-407V), the controller 1400 sets the resonant frequencyof the resonant power converter 1500 to a value associated with gainfunction 3223. In each of the different ranges, in a manner aspreviously discussed, the controller 1500 adjusts the switchingfrequency Fsw1 and implements hysteresis if the output voltage 1230changes over time.

FIG. 33 is an example diagram illustrating operation of a resonant powerconverter in a semi-regulation mode with changes to a resonant frequencybut with optimized resonant tank circuit according to embodimentsherein.

In contrast to previous FIG. 32, FIG. 33 shows an optimized resonanttank with a flatter gain curve. Such an optimization reduces the amountof resonant current in the tank and increases the efficiency of theconverter.

As shown in graph 3310, in a manner as previously discussed, embodimentsherein include implementing different optimized gain functions (G=Gain)over a range of different input voltages. For example, when themagnitude of the output voltage 1230 is greater than a threshold valueVoutth1 (such as when the output voltage falls in a first range), thecontroller 1400 sets the resonant frequency of the resonant powerconverter 1500 to a value associated with gain function 3321; when themagnitude of the output voltage 1200 is between threshold value Voutth1and Voutth2 (such as when the input voltage falls in a second range),the controller 1400 sets the resonant frequency of the resonant powerconverter 1500 to a value associated with gain function 3322; when themagnitude of the output voltage 1230 is less than threshold valueVoutth2 (such as when the input voltage falls in a third range), thecontroller 1400 sets the resonant frequency of the resonant powerconverter 1500 to a value associated with gain function 3323. In each ofthe different ranges, in a manner as previously discussed, thecontroller 1500 adjusts the switching frequency Fsw1 and implementshysteresis as the input voltage changes over time.

Note again that techniques herein are well suited for use in switchingpower supply and resonant power converter applications. However, itshould be noted that embodiments herein are not limited to use in suchapplications and that the techniques discussed herein are well suitedfor other applications as well.

While this invention has been particularly shown and described withreferences to preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the spirit and scope of the presentapplication as defined by the appended claims. Such variations areintended to be covered by the scope of this present application. Assuch, the foregoing description of embodiments of the presentapplication is not intended to be limiting. Rather, any limitations tothe invention are presented in the following claims.

The invention claimed is:
 1. A power system comprising: a monitorresource operative to monitor a magnitude of a voltage at a node of aresonant power converter; a controller operative to, depending on themagnitude of the voltage at the node, dynamically control a respectivegain provided by the resonant power converter; wherein the controller isfurther operative to: depending on the magnitude of the voltage, and toprovide the respective gain, adjust a resonant frequency of the resonantpower converter; and wherein the controller is further operative to: i)detect a first voltage range in which the magnitude of the voltageresides, the first voltage range being one of multiple voltage rangesassociated with operation of the resonant power converter, ii) identifya resonant frequency setting assigned to the first voltage range, andiii) control the resonant power converter to operate at the identifiedresonant frequency setting.
 2. The power supply as in claim 1, whereinthe controller is further operative to determine a switching frequencyin which to control switches in the resonant power converter based on acombination of the resonant frequency of the resonant power converterand the magnitude of the voltage at the node.
 3. The power supply as inclaim 2, wherein operation of the resonant power converter at theresonant frequency and the determined switching frequency is operativeto control the respective gain of the resonant power converter.
 4. Thepower system as in claim 1, wherein the controller is further operativeto map the magnitude of the voltage to a switching frequency value andset a switching frequency of controlling switches in the resonant powerconverter to the switching frequency value.
 5. The power system as inclaim 1, wherein each of the multiple voltage ranges is assigned adifferent resonant frequency setting.
 6. The power system as in claim 1,wherein the controller is operative to set a magnitude of a switchingfrequency of operating switches in the resonant power converter to afixed value; and wherein the controller is operative to vary a magnitudeof a resonant frequency of the resonant power converter depending onvariations in the magnitude of the voltage.
 7. The power system as inclaim 6, wherein each voltage range of the multiple voltage ranges isassigned a different respective resonant frequency setting.
 8. A systemcomprising: a circuit board; the power system of claim 1, the powersystem being a power supply fabricated on the circuit board; and a load,the load powered via power provided by the resonant power converter. 9.A method comprising: receiving a circuit board; and fabricating thepower system of claim 1 on the circuit board, the power system being apower supply operative to output power subsequently used to power a loadaffixed to the circuit board.
 10. The power supply as in claim 1,wherein the voltage is an output voltage of the resonant powerconverter.
 11. A method comprising: monitoring a magnitude of a voltageat a node of a resonant power converter; to set a respective gain of theresonant power converter, dynamically selecting a resonant frequency ofthe resonant power converter depending on the magnitude of the voltage;and controlling switching of switches in the resonant power converter ata switching frequency; wherein a voltage range associated with thevoltage at the node is divided into multiple voltage ranges, each of themultiple voltage ranges assigned a resonant frequency setting of thepower converter; wherein the multiple voltage ranges include a firstvoltage range and a second voltage range, the first voltage range beingassigned a first resonant frequency setting, the second voltage rangebeing assigned a second resonant frequency setting; and wherein therespective gain of the resonant power converter is a piece-wise gainfunction including a first gain function associated with the firstvoltage range and a second gain function associated with the secondvoltage range.
 12. The method as in claim 11 further comprising:selecting a magnitude of the switching frequency based on a combinationof the resonant frequency and the magnitude of the voltage.
 13. Themethod as in claim 11, wherein controlling switching of the switchesincludes: mapping the magnitude of the voltage to a switching frequencyvalue; and setting the switching frequency of controlling the switchesin the resonant power converter to the switching frequency value. 14.The method as in claim 11 further comprising: controlling the resonantfrequency of the resonant power converter to be a fixed resonantfrequency setting during conditions in which the magnitude of thevoltage resides within the first voltage range of the multiple voltageranges; and while the resonant frequency of the resonant power converteris set to the fixed resonant frequency setting, adjusting a magnitude ofthe switching frequency as the magnitude of the voltage varies withinthe first voltage range.
 15. The method as in claim 11 furthercomprising: while a magnitude of the switching frequency applied to theswitches is set to a fixed frequency value, varying a magnitude of theresonant frequency of the resonant power converter depending onvariations of the magnitude of the voltage.
 16. The method as in claim11 further comprising: producing map information providing a mappingbetween the magnitude of the voltage at the node and a setting of theswitching frequency to be applied to the switches in the resonant powerconverter.
 17. A method comprising: monitoring a magnitude of a voltageat a node of a resonant power converter; to set a respective gain of theresonant power converter, dynamically selecting a resonant frequency ofthe resonant power converter depending on the magnitude of the voltage,the dynamic selecting including: i) detecting a first voltage range inwhich the magnitude of the voltage resides, the first voltage rangebeing one of multiple voltage ranges; ii) identifying a resonantfrequency setting assigned to the first voltage range; and iii)controlling the resonant power converter to operate at the identifiedresonant frequency setting assigned to the first voltage range; themethod further comprising: controlling switching of switches in theresonant power converter at a switching frequency; wherein controllingswitching of the switches includes: i) mapping the magnitude of thevoltage to a switching frequency value; and ii) setting the switchingfrequency of controlling the switches in the resonant power converter tothe switching frequency value.
 18. The method as in claim 17, whereineach of the multiple voltage ranges is assigned a different resonantfrequency setting.
 19. A power system comprising: a monitor resourceoperative to monitor a magnitude of an input voltage at a node of aresonant power converter; a controller operative to, depending on themagnitude of the input voltage at the node, dynamically control arespective gain provided by the resonant power converter to convert theinput voltage into an output voltage; and wherein the controller isfurther operative to: i) control a resonant frequency of the resonantpower converter to be a fixed resonant frequency setting duringconditions in which the magnitude of the input voltage falls within afirst voltage range; and ii) vary a magnitude of a switching frequencyapplied to switches in the resonant power converter depending on themagnitude of the input voltage within the first voltage range; whereinthe controller is further operative to: select the fixed resonantfrequency setting in response to detecting that the magnitude of theinput voltage resides in a first voltage range, the selected fixedresonant frequency setting assigned to the first voltage range; andoperate the resonant power converter at the selected fixed resonantfrequency setting.
 20. The power supply as in claim 19, wherein thecontroller is further operative to determine the switching frequency inwhich to control the switches in the resonant power converter based on acombination of the resonant frequency of the resonant power converterand the magnitude of the input voltage at the node.
 21. The power supplyas in claim 20, wherein operation of the resonant power converter at theresonant frequency and the applied switching frequency is operative tocontrol the respective gain of the resonant power converter.
 22. Thepower system as in claim 19, wherein the controller is further operativeto map the magnitude of the input voltage to the switching frequencyvalue and set the switching frequency of controlling switches in theresonant power converter to the switching frequency value.